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The Postal Service plans to stop delivering regular mail on Saturday. Mathematician Curtis Cooper talks about his discovery of the longest prime number. Thousands of people who had their homes destroyed by Hurricane Sandy four months ago are still living in hotel rooms, rentals or crashing with friends and family. A new startup aims to help those without bank accounts or credit cards pay for stuff online. As Hasbro gets rid of the iron token in its Monopoly game, we look at the innovations behind the iron’s real-world demise. And In the latest installment of Freakonomics Radio, Kai Ryssdal recalls some memories in a conversation with Stephen Dubner -- only to find out how deceiving our minds often are.